Supergravity and a confining gauge theory: Duality cascades and χSB-resolution of naked singularities

We revisit the singular IIB supergravity solution describing M-fractional 3-branes on the conifold [hep-th/0002159]. Its 5-form flux decreases, which we explain by showing that the relevant N = 1 SUSY SU(N + M) x SU(N) gauge theory undergoes repeated Seiberg-duality transformations in which N → N - M. Far in the IR the gauge theory confines; its chiral symmetry breaking removes the singularity of [hep-th/0002159] by deforming the conifold. We propose a non-singular pure-supergravity background dual to the field theory on all scales, with small curvature everywhere if the 't Hooft coupling gsM is large. In the UV it approaches that of [hep-th/0002159], incorporating the logarithmic flow of couplings. In the IR the deformation of the conifold gives a geometrical realization of chiral symmetry breaking and confinement. We suggest that pure N = 1 Yang-Mills may be dual to strings propagating at small g_sM on a warped deformed conifold. We note also that the standard model itself may lie at the base of a duality cascade.